Tire Technology 101

It these modern times with almost endless high performance, specialty tire choices for trucks, cars, and motos, it’s easy to forget how far we have progressed in just the past few decades. Prior to the 1980s there were few enthusiast, recreational off-highway truck tires.

As trucks and tires have advanced to a very high level many are now focused on the toughest tire available, thinking this is the best option. Maybe so, if you are continually puncturing your tires and/or ripping sidewalls, maybe you do need the toughest tire. However, some have forgot or never knew that the problem with light-truck tires just a few decades ago was that most were bias-ply designs and were very inflexible. They were pretty rugged as bias-ply tires tend to be, but in addition to their limiting tread designs, on-highway handling was only fair, and sidewall and tread flex, a key component of traction, was almost non-existent. Radial tire design and the specialty tires have changed this in a big way.

This comical and entertaining historic advertising movie from 1939 for the Fisk Tire Company illustrates how advanced tire technology has become and how different it was decades ago. At minute 4:00 in the video, the narrator explains how the rubber “inserts” allow the formerly continuous tread ribs to flex and act independently. This is essentially the same as what’s accomplished with the siping of modern tires, allowing tread blocks to conform and move independently, and providing biting edges for grip. Flexibility is key. If you want traction, you need flex. Most modern tires do offer a lot of flex, and flexibility is part of the reason handling, ride, and traction is so good (think radial tires). It’s important to remember and focus on the fundamental principles of traction and drivability.

Copyright © 2012 James Langan

No Dakar Rally for North America?

I’m not much of a racing fan, or even a sports fan. It’s not that I don’t appreciate the skill of athletes, I do, but it’s never been my thing to watchsports. Though a few years ago I got hooked on watching the excellent Dakar Rally video coverage on sbs.com.au. At the end of each day in early January, I would watch all the SBS videos featuring the bikes, quads, cars, and trucks.

After two days of not being able to play the 2012 productions, a Google search indicates viewers from the United States and Canada (maybe others too) are not able to view these shows. 🙁

This is probably because another network has the rights to coverage for the U.S. and Canadian markets, but I’ve yet to learn the reason or a suitable substitute for the comprehensive SBS coverage. Maybe the videos will be viewable when the race is over?

Oh well, I guess it’s time get back to doing and not spend so much time watching during the first two weeks of the year. Thanks for the butt kick forward, it’s time to get back to working [playing] with trucks and motos.

RoadTraveler – Rolling Forward

Copyright © 2012 James Langan

Static Balance Details

Got Wheel Weight?

A reader asked a few good questions, see below.

Q. Via this balancing method, did you reduce the amount of weight required? 

A. In general, static balancing methods reduce the weight needed to balance a tire/wheel combination, and this is true for both bubble balancing and machine static balancing. Static balancing only balances a tire and wheel in one plane, vertically. More weight is needed for a dynamic balance, partially because dynamic balancing also helps correct lateral imbalance.

The amount of weight needed to balance a tire using this bubble balancer appeared similar to a machine static balance. Maybe slightly more weight and less precise.

Q. Have you tried rotating the tire on the rim to minimize added weight?

A. While using this bubble balancer there was no need to rotate the tires on the wheels, the weight needed to balance was not excessive once I was competent. Obviously it’s not easy for a man working with hand tools to breakdown a tire and rotate it on a wheel. However, many times in the past while having tires machine mounted & balanced I’ve had the tires rotated on the wheel. This was done is response to a tire/wheel combination that required more weight than I thought should be used.

How much is too much? That depends on the wheel (size, aluminum vs. steel) and the size, weight, and tread of the tire. I’m generally very particular and don’t want to feel any tire imbalance from a warmed-up tire. For my trucks, all of which currently run 33-inch tires, I’m typically happy if less than six ounces are needed for a static balance. Generally a few more are needed for a dynamic spin balance. When a new tire starts needing more than 8-9 ounces (dynamic) I like to rotate the tire on the wheel 180-degrees, hoping less weight will be required. This doesn’t always work, and sometimes the tire must be returned to its original position. The weight mentioned above are personal maximums, less weight is better. Regardless of the weight needed, more important is the quality and repeatability of the balance.

Q. Have you tried balancing the rim by itself? 

A. I’ve checked the balance of wheels without tires, though I’ve never actually needed balance a wheel without a tire mounted. Checking the balance of a wheel has invariably showed that either the tire or the balance machine was the source of a problem, but of course wheels can be damaged. I’ve been using light, factory aluminum wheels and moderate sized tires for many years, and been lucky my heavily used wheels remain true.

Copyright © 2011 James Langan

Finding Balance

Going off what little I could remember, what my friend Paul remembered, and reading what a few old-timers had to say about the lost art of bubble balancing, I started what became a long weekend project. It seems I’m not the only one who wants to remember and/or practice the old ways, as one thread I found on www.GarageJournal.com had only been dormant for about eight months. It was helpful enough that I decided to register for the forum and post a thank you comment.

I balanced and then rebalanced each tire a few times. Initially I was not exacting enough (unusual for me), or maybe patient enough. Using a bubble balancer is not the most technical, modern balancing method, and tolerating a half a bubble off is not okay, patience and precision are critical.

But there was much more to it than that. In addition to being patient and waiting minutes for the spirit level bullseye to settle before and after adding weights, there was the challenge of which method to use, this is what took so long. Learning. Several hours of attempting to adequately balance my tires, trying most of the methods a few times on each wheel.

Split the necessary weight on the inside and outside of the wheel but directly inline with the heavy spot on the other side of the tire? Or use the method that was patented by BADA of moving the necessary wheel weight out to approximately 3 & 9 o’clock opposite the point of imbalance? Of course testing the quality of the balance job requires putting the tires on the car and actually driving. For any of these techniques to work you must first level the balancer.

Experimenting with the BADA method.

Ultimately I had the most success putting tape-weights 180-degrees across from and directly inline with the heavy spot, on the inside of the wheel. This is the same groove my tire shops had been using for my machine, static balance. If the tire/wheel combination needed 4 ounces, I centered the strip of tape-weights opposite the heavy spot. This did help spread the weight over a larger area of the wheel, though not as much as using the BADA method.

Simple static method

After getting closer and better, I started focusing on the fronts and refining my skills. Discovering that one of my older FC II tires that had already logged 10,000-miles on the right side of the car, didn’t want to be run on the left helped tremendously. I eventually decided that the two new tires would go on the same axle, the front, and not on the left side of the car as I had hoped would work.

Should I start manually changing my tires? My friend Paul’s recent experience changing much smaller vintage Willys MB tires with spoons makes me think not. He tore his bicep.

RoadTraveler    rollin’ forward

Copyright © 2011 James Langan

Don’t Tolerate Half A Bubble Off

Cooper S/T 255/85R16D on bubble balancer

My friend Paul had a bubble balancer that his father purchased new about twenty years ago, and was willing to lend it to me. They used the balancer on a regular basis to maintain their tires when dad, mom, brother, and sister were all driving thousands of miles a month as couriers. It seemed like an interesting idea, and since I typically have my tires spin balanced using the static (single plane) method, which uses less weight and seems to work well for heavy light-truck RV tires (as they used to be called) I decided to give it a try.

This is one of those things that is better written about a few weeks after the exercise, as the hour-by-hour, day-by-day report would have been a bit too much to share, and would have covered your screen with dirt, sweat, and a few expletives. Like any new skill, there was a learning curve. I’d actually used a bubble balancer about twenty-five years ago when I briefly worked in a tire shop during my youth. Back then, the bubble balancer was only used for the thrifty folks who purchased a tire and didn’t want to pay for a machine spin balance. I didn’t bust tires long enough to become a bubble balance expert, and whatever knowledge I once had using a bubble balancer had long since faded and I was starting over.

Computers are surely a blessing and a curse, but when it comes to finding information the web is an invaluable resource. I can’t imagine having to go to a library and search through volumes of old books and magazines to find information on using a bubble balancer. Though like many things on the web, one must sift through the many of opinions hearsay to find proven techniques that work. It turns out there is more than one way to use a bubble balancer, and one of the methods was even patented!

Copyright © 2011 James Langan

A New Tire or Two

Old TXR 255/85R16D spare and a Not so old Dick Cepek F-C II 285/75R16D

Several weeks ago I cut a sidewall on one of my LT285/75R16 Dick Cepek Fun Country II (FC II) tires. The story about the sidewall cut and trail will be told later, but with only three FC II treads on the 4Runner I was in need of at least one new tire. Since I had been running a close enough 255/85R16 spare, I decided to buy two FC II to insure I had the exact tire in the unlikely event I ruined another casing in the near future. My calculations indicated that if I rotated the older three tires on one side of the car, all with 3/32″ of wear, and the two new ones on the other side, the wear would even out over the next 30,000-miles.

Most tire warranties don’t cover off-road use. This is term is open to interpretation, as many state and county roads in the rural west are not paved but are still very clearly roads. Regardless, since the three older FC II treads had been purchased mail-order and were not covered under any road hazard warranty, I decided to buy the new tries mail-order as well. One of the local tire shops I do lots of business with would have mounted & balanced the new treads for a reasonable fee, but I decided to play with a little old school technology and balance them myself. It wasn’t easy.

Copyright © 2011 James Langan

From The Wheels UP

I’ve yet to post anything of substance about tires, but amongst my gearhead buddies I have a well-earned reputation as a light-truck tire aficionado. This started a few years ago when I was writing several articles a year for the Power Stroke Registry magazine, including a few tire reviews. It continued with a new Jeep, then a couple Toyotas, and in addition to my own wear data I’m collecting information from a couple guys running my favorite tread. But this is not a post about tires, it’s even more primal than truck tires; it’s about wheels.

Unless you want to constantly swap new tires on one set of wheels, the best way to test tires is to have more wheels. We have plenty of spare wheels for the older trucks in our small fleet of 4x4s, but the newest rig had only the set it came with. I was not actively looking for wheels when my friend Charlie sent me a message saying there were some wheels for my truck on our local Craigslist.

According to the advertisement these Toyota take-off wheels were previously listed for $500.00, far too much money in my book and that’s why he hadn’t sold them. The seller’s ad also mentioned how much the wheels would cost new from a dealer, which is irrelevant. The seller now had the rims listed for $375.00 or-best-offer. This was still more than I was willing to pay, and the rims were located in about 60-miles away. Considering the time and gas it was going to consume to procure them, I was willing to offer him $250.00. Like another buddy said, “all he could say was no”.

Right before I picked up the phone my new voice of frugality—which has been fighting for a place in my head, and likes to spar with the devil of buy-it-now—whispered in my ear; “what if there is a better set for sale, you better be sure before you buy.” I proceeded to read through all of the results for Toyota wheels, looking for a better deal. On the sixth and last page, listed over a month prior, was a set of wheels for $300.00, or-best-offer. These were the same 18×8″ size, but a different style Toyota aluminum wheel which I actually preferred, and instead of 60-miles away they were literally 1.5-miles near.

So I called the guy, confirmed he still had the rims and told him my situation. Essentially that I wasn’t looking to buy wheels but a buddy had told me to look on Craig’s List, and with a chuckle said, “We all know what that can lead to”. The gentleman said he had actually forgot they were listed on Craig’s List until that very morning, they had been for sale for over a month, and he probably needed to re-list them. Like many he had removed them because he added a spacer lift and new aftermarket rims to his truck, after they logged a mere 13,000-miles. I asked him if he would consider $200.00 and he said sure. I went to the bank and a couple hours later I was giddy with new wheels.

Copyright © 2011 James Langan